How did they make ice cream before refrigerators?

And the history of ice cream


Hemant here. Technology, migration and explorations have tremendously changed what we eat. Today’s essay is an example of how.

Ice cream is one of the most wonderful human creations. Today, ice cream is a $66 bn industry, and is still growing. But when it started spreading around the world, it wasn't meant for everyone to consume.

It was considered a royalty, until some enterprising individuals decided to make it available for the masses, very much similar to the history of sugar.

So, what does the history of ice cream look like? And how exactly did they make ice cream before refrigerators existed?

Let's check it out...

The origins of ice cream

Like almost every other food on the planet, there is no single person who invented ice cream. However, we see that back in 200 B.C., people in China had started creating a dish of rice and milk, which they froze by packing in snow.

Tadaa - the earliest variant of ice cream was born. How they arrived at this combination seems like a result of a lot of hit and trial. Most food we eat today has evolved over decades, if not centuries. Ice cream is no different in that regard.

The Chinese kings started filling pots with milk and syrups, and placing them in the snow in order to freeze them.

It is also known that the rulers around this time indulged in desserts of snow. Alexander the Great enjoyed eating snow flavoured with honey.

But, these desserts were restricted to the royalty. Ice cream was not a widely known product yet.

Spreading across the world

And then came the time of the European explorers. Some sources suggest Marco Polo brought back ice cream recipes from China to Italy. However, this could be a made-up story.

Nevertheless, the point being, ice cream travelled to Europe, where it became a desert for the royalty. These royal people frequently hosted other kings and queens, and with a thing like ice cream, it was obvious that things would spread!

And yet, it is alleged that some of the royalty tried to keep the ice cream recipe a secret!

But good things eventually spread in the world. And so did ice cream. Cafe Procope in France started serving Ice Cream to the general public in the late 17th century. They made this ice cream using milk, cream, butter and eggs.

And then, ice cream arrived in America. The earliest known mention of Ice Cream in America is in 1744. And the American elite loved the delicacy. President George Washington is known to have spent $200 (about $3000 today) in 1790 alone on Ice Cream!

Then America, being America, started commercializing the product like anything.

However, there was still a big problem. Refrigerators didn't exist. So production was slow, and consumption had to be quick, otherwise:

This changed when in 1870, Germany invented industrial refrigeration. And it had a catalytic effect on the industry. Then came the invention of cones, hundreds of flavours and varieties of ice creams, and so on.

Long live ice creams!

In another part of the world

Europe and America were not the only places where ice-cream was created and consumed. In the 16th century, "kulfi" started becoming popular in India.

The word Kulfi is derived from Farsi. Kulfi means "covered up". Flavoured with pistachios, saffron, and other dry fruits, Kulfi was usually surved in small matkas which would allow it to be stored for longer and prevent it from melting.

But in India, especially in Delhi, where the rulers had their capital, there was no snow to freeze ice cream. So how did they make ice cream in the sweltering Delhi heat? Some sources suggest they transported Himalayan ice to warmer regions, but I don't believe that would have been enough.

But they knew how to freeze ice cream.

Okay, back to chemistry. How is ice cream frozen?

The basic idea of how ice cream has remained the same over the years.

You fill up a bucket full of ice, then place a pot of cream, sugar and whatever flavour of ice cream you want. Then you add some salt to the ice. Let the magic happen!

What actually happens in this process?

Salt, as you might know, lowers the freezing temperature of ice. This is also the reason why salt is poured over snow-covered streets in the winter.

Now, because the freezing point of ice is lowered, it needs energy to melt.

And where does it get that energy from? Surprise, surprise! From our pot sitting in the middle. It starts sucking out the heat from the pot, resulting in the pot and its content cooling down (and freezing) while the ice outside starts melting - however, the melting is very slow.

And you can use this same process to make more ice, so once you have some supply of ice, you can continue to make ice and ice cream.

This principle was the primary way in which ice cream was made, until the advent of refrigerators.

Earlier on, "saltpeter" was used instead of salt to freeze Kulfi. At the time, saltpeter was used for making fireworks and gunpowder. It is likely that someone stumbled upon its freezing properties.


  1. The History of Ice Cream (

  2. The story of Kulfi - STORY OF THE KULFI (

  3. Saltpeter for making ice cream - How Did They Make Ice Cream in the 17th Century? (

Thank you for reading

The history of things around us can sometimes be fascinating, and if you have friends who would love to learn about these with me, do share this with them.

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If you have any topic you want to learn about, let me know. We can learn together.

Thanks for reading :)


#50: A sport that relies on technological innovation

Formula One - where every micro-second counts.


Hemant here. Through this email, my goal has been to reflect on how technology is affecting our lives - both at a macro and a micro level.

Today’s essay is a good one, and it sticks to the theme very much.

I’m going to talk about one of my favourite sports in this world - Formula One. Though the sport gets a name for being a “rich man’s sport,” I think this image tends to belie the decades of technological progress we’ve made in automotive technology, which has made the world a safer place to live in.

Let us begin…

What exactly is Formula One?

In a nutshell, Formula One is a car racing championship, where 10 teams compete every year for the World Championship. Cars drive fast, like this —

Each race lasts about 2 hours of total time, preceded by many many hours of preparation and years of training. In short, it is like any other worldwide sport - you train for years and prepare for matches lasting a few hours.

The “Formula” in Formula 1 stands for a series of rules that all participants have to adhere to. These rules are decided by a governing body called FIA, which creates rules not just for F1, but also for Formula 2 and many other racing championships.

The first F1 championship was held in 1950, and was originally dominated in Europe. The FIA in the recent decades has made a concerted effort to take the sport global, and now races are held across the world.

Alright, so what’s different?

Let’s look at some facts —

  1. Today, the cars can have a top speed of about 325 kmph.

  2. Cars can go from 0-150kmph and back in less than 4 seconds.

  3. Drivers can lose up to 6kgs in a single race! Wait, what?

  4. Team yearly budgets run upwards of $100 million, with several teams spending more than $400 million dollars every year.

  5. Depending on the tyres used, a car can’t go for more than 30-40 laps (1 lap = around 5 to 6 km, depending on the track). Cars often have to take a pit stop to change their tyres.

  6. Micro-seconds count. A driver can take 1/1000th of a second more than another driver, and thus be judged to be behind the other driver.

And what about the drivers?

Well, they are incredible athletes to say the least. Unlike driving a normal car, here’s some things they experience:

  1. While turning and braking, the G-force they experience can be 4 to 5G. This is basically 4 to 5 times the regular gravitational force of the earth. This is similar to the G-force experienced by flight pilots who do rapid somersaults. These G-forces can make you faint if you’re not trained to handle them. F1 drivers have to specifically train to ensure they can handle such stress on their bodies.

  2. A single lap could have 19-20 turns, which means that every second, you might be turning your car in a different direction, while decreasing your speed from 300 kmph to 100 kmph, while also looking around to make sure no one is overtaking you, and also trying to communicate with your team about your car’s status. Well, talk about peak performance…

  3. The drivers also have to juggle a lot of moving parts in their cars. Take a look at the steering wheel itself. There are so many buttons and knobs on it that you have to click on within seconds that mistakes are easy to make, unless you are hyper-focused.

    1. Not to mention the biggest risk these drivers face - that of losing their lives. A single wrong push of the pedal or cranking of the steering wheel could crash your car. Over the years, several people have died driving an F1 car.

😱That seems like a lot of risk.

It is. In the second last race of the 2020 season, Romain Grosjean’s car pierced through the barricades and went beyond the racing track limits, before bursting into flames. While several people had started to lose hope, like a phoenix, Romain walked out of the burning fire and towards an ambulance waiting for him.

Thanks in part to the decades of innovation in safety - the fire suits, the design of F1 cars that minimizes impact on the driver, the design of the circuits to ensure that other drivers are safe, the hundreds of safety protocols, and of course, sheer luck!

Check out this video to see the miraculous escape.

But the game goes on, just like life! Over the decades, FIA has heavily invested in making the sport a lot more safer. A recent example is the halo design on top of the cockpit, which prevents drivers from damaging themselves. It is suggested that the halo played a major role in saving Romain Grosjean’s life as well.

Why is F1 called a team sport?

Just like every car has tens of thousands of moving parts, a driver cannot win without the adequate support of his team.

During a race, there is a lot more going on behind the scenes while the driver is trying to win. For example - there are people monitoring data about how the car is behaving, some who are observing the competitors and optimizing their strategy, and so on.

Drivers also often have to pit during a race. Nowadays, pit stops last 2 seconds and are a key part of racing strategy for any team. Take longer than that, you lose your spot. Avoid a pit stop, and you might gain a few spots. Of course, this is easier said than done. There are several variables at play here.

Let’s take an example of how things could fail. In the 2021 Monaco Grand Prix, Valteri Bottas was driving in the second place when his team decided to change the car’s tyres. He drove into the pit lane.

But guess what happened?

One of the guns that unscrews the tyre from the axle got jammed! As a result, the existing tyre could not be removed from the car, as Bottas helplessly watched towards his pit crew trying to remove the tyre.

In the end — Bottas had to end his race. Quite a bad result for someone who was in the second spot and had a real chance of winning the race!

Technological innovation aided by sport

You might have guessed by now that the sport requires a lot of technological innovation by the teams in order to win races. This, in fact, improves our cars on the road.

Let’s take a few examples —

  1. KERS (Kinetic Energy Recovery System) — introduced in the late 2010s, this system allowed the energy generated from braking to be stored and reused to give the cars an additional push when they had to overtake. Today, this same system is used in a lot of hybrid cars and buses, which helps make our cities greener.

  2. Data transmission and monitoring — Public transportation has also seen benefits of innovation coming from Formula One. Singapore’s Mass Rapid Transit system now uses sensors and data tools that once were introduced in Formula One.

  3. Innovation in materials — The innovations in aerodynamics and materials engineering have found their way to other sports like cycling and sailing, where aerodynamics play a huge part in improving performance.

In conclusion…

Humans are motivated by games and competition. By adding technology as a key requirement for playing these games, F1 has helped us make some serious technological prowess.

A lot has happened and a lot is yet to be seen, but as I write this essay, my love for the sport has only grown!

I am once again (unrealistically) dreaming of the day I get to drive an F-1 car…😉

Want to learn more about F1?

  1. A newbie’s guide to Formula One - A good article that will help you know all you need to if you want to start following the sport.

  2. Formula 1 - Drive to Survive: An excellent docuseries by Netflix covering the behind-the-scenes of Formula One.

  3. Formula 1 official site: Look through the history of Formula One, its technology, and everything else.

Was this essay useful to you? Do share your feedback by replying to this e-mail.

Thanks for reading :)


#49: The darker side of cryptocurrencies

Book notes - American Kingpin & the nefarious uses of cryptocurrency, and more


Hemant here.

Mark Twain famously quoted —

Truth is stranger than fiction, but it is because fiction is obliged to stick to possibilities, truth isn’t.

In other words, fiction has to always make sense, but truth doesn’t. This is one of the biggest paradoxes in life. When we create stories, they have to be logical, otherwise, they don’t stick very well. But the truth is usually a series of random events.

Last week, I found a good example where actually a non-fiction book was just as good as a fiction book. While reading the book, I kept thinking about the quote above. I wondered whether the book was actually non-fiction or whether it was the truth!

But I was convinced that it was the truth when the author listed all his research materials and artifacts towards the end of the book.

The book I’m writing about is American Kingpin by Nick Bilton —

In the last decade, cryptocurrencies have been touted as the future of how currencies work. Their lack of dependence on governments, but on computers, makes them much more reliable.

Yet, there are some big problems with them (at least right now). The privacy makes it near impossible to trace who actually owns what, even though all the transactions that happened are available on a publically viewable ledger.

And thus, they can be used for any number of nefarious purposes.

Then there is the concept of The Dark Web, which basically means websites that are hidden from the view of search engines like Google. This portion of the web also keeps you hidden from governments and security agencies, which means you can be free to do what you want.

This is exactly what Ross Ulbricht, founder of The Silk Road did. He created an e-commerce portal for drugs and later expanded it to guns. People could easily buy and sell drugs, and pay each other using bitcoin. The site grew like anything, making Ross a millionaire within months of starting it.

Of course, wouldn’t the governmental agencies be irked?

The book follows the story of officers of different governmental agencies, the FBI, the DEA, and the US Customs department trying to nab Ross for operating the Silk Road.

Ultimately, what was thought to be impenetrable was given away by a series of errors made by Ross.

If you like reading Crime thrillers, do check the book out.

Other things I came across…

  1. The Value of time: One of the biggest truths of adulthood is the need to manage your time. Between work, friendships, relationships, and our passions, we are trying to juggle a lot already. So, how do you allocate your time so that you reduce wastage? In this essay, James Clear suggests a technique to calculate the value of an hour you spend. Based on this, you can determine whether you should do it yourself, or pay someone to do the work. For example: if the value of your time is ₹1000, James suggests that you should pay ₹500 for something that takes more than half an hour.

    Though I have my reservations about measuring time spent this way, this article is certainly thought-provoking. Do check it out!

  2. Blogging his way to $9mn in cash — I recently heard this podcast episode, where a non-writer, non-blogger started a blog in a subject he had no expertise around: daily soaps on TV. He claims to have never seen a single daily soap episode. And guess what, not only he started it, but he was also able to sell it for nearly $9mn! This is another story that shows the power of the internet.

That’s it for today!

What did you think of this email? Do let me know if you like it, or even if you don’t.

Thanks for reading :)


#48: The importance of "showing" your work

Especially today, when the discovery of new people and content happens online


Hemant here. Some of you might be receiving this email because you subscribed to the Easy But Hard series or because you downloaded my book. Don’t worry, your email address is safe :)

I’ve unified all my different “email lists” into a single one.

By having a single email, you will receive not only my short stories, but also some other cool things - like notes on books, interesting stories on the internet, and my learnings from writing for 6+ years.

If you don’t want to receive these emails, feel free to unsubscribe by clicking the link at the bottom of this email. No hard feelings, I promise.😄

I recently had a chance to read the book - Show Your Work, by Austin Kleon. To say that the book has been an eye-opener will be an understatement.

Barely a hundred pages long, this was the book I needed at this time.

As you might know, I have been thinking about what to write consistently, now that I’ve finished the Level Up series. This book helps me create a system for my overarching strategy towards writing. I’ll share more about it in a few weeks.

But, without further rambling, here are some key takeaways from the book:

On sharing your process

An excerpt from the book —

We’re not all artists or astronauts. A lot of us go about our work and feel like we have nothing to show for it at the end of the day. But whatever the nature of your work, there is an art to what you do, and there are people who would be interested in that art, if only you presented it to them in the right way. In fact, sharing your process might actually be most valuable if the products of your work aren’t easily shared, if you’re still in the apprentice stage of your work, if you can’t just slap up a portfolio and call it a day, or if your process doesn’t necessarily lead to tangible finished products.

I’ve been writing fiction consistently for more than 6 years at this point. But I’ve always struggled to build an audience. The reason - I absolutely detest “marketing” what I write. Sure, I can go and post a link on social media, but it is not a natural strength of mine to go to a thousand people and talk to them about my book. It feels like I am boasting about my book.

The paragraph above changes that for me. It basically says that there is always something you can share about what happens behind the scenes, and this information will help you find your audience.

As I pondered about what I could share with others, I realized that there’s actually quite a bit. For eg: having published 2 books and several short stories, I can share my journey of publishing, what I have learned in the process and how these learnings could benefit others.

Earlier this year, I had written a long post about all of my online “experiments”. I think that is the right approach to sharing content. Expect a lot more of these.

Also, as I write more short stories, like the Level Up series, I realize that writing “Behind the Scenes” is actually important. The reason —

No, words don’t speak for themselves

Artists love to trot out the tired line, “My work speaks for itself,” but the truth is, our work doesn’t speak for itself. Human beings want to know where things came from, how they were made, and who made them. The stories you tell about the work you do have a huge effect on how people feel and what they understand about your work, and how people feel and what they understand about your work affects how they value it.

This was a big realization. If you think more about it, any specific moment you remember is special because there’s a story associated with it. For example, you wanted something desperately, you achieved it. How you did it makes up the story. And this is the reason why you remember that photo you took, or that cake you baked, or the joke you thought of!

By telling the stories behind my stories, I hope to share my process, and in turn, gather like-minded folks.

Here are the 10 things the book talks about in detail:

To conclude…

Make stuff you love and talk about stuff you love and you’ll attract people who love that kind of stuff. It’s that simple.

No explanation needed!

To learn more about the book here’s a detailed summary, or you can find the book on Amazon.

Some other cool things I came across this week —

  1. A brief history of Dogecoin: the cryptocurrency that began as a joke, and was then pumped to exorbitant amounts, before falling down again. This story even includes an introduction to cryptocurrencies, so don’t be scared. This post is from one of my favourite publications called Simplanations. Subscribe to their work if you like it.

  2. Tokri - a short film: Within 15 minutes, this short film took me to a different world and had me root for the little girl in the story. Also, this is some top-class stop motion animation. I suggest watching Behind the scenes video of this as well!

Before you go, I have one question for you. I’m considering renaming this publication to something else. “Zoom In, Zoom Out” seems too formal and doesn’t evoke much joy.

Do you have any ideas in mind for what I should name it? Reply and let me know.

Thanks for reading :)


Writing short stories & what's next

#48: Learnings from the Easy But Hard story collection


It’s been a while since I sent an email. As some of you might know, I’ve been writing a story series since February called Level Up. It’s the story of a person unexpectedly getting promoted, and being unable to handle the pressure that comes with it.

But instead of writing this as a novel where I would publish everything at once after I finish writing, I decided to publish a chapter every week. Here's how the experiment went:

Where did I start?

When I started writing the Level Up series, the goal was to validate whether a series would engage people better for a weekly delivery format, as compared to writing one-off short stories every week.

And in the process, I would also validate my material for longer formats - series, books, films.

Surprisingly, each of the 10 episodes has been shared at least once. When I was writing one-off stories before this, such consistent sharing never happened.

Whether it is just one person sharing all of them, or more sharing once, I don't care.

The important part - people were sharing the stories.

And at the same time, I've connected with new people who read and gave me good feedback.

Some even pointed out mistakes in the story! I take this positively!

Going back to the original goal:

  • Has the content engaged people more? Yes!

  • Have I gotten feedback for longer material? Yes!

Initially, I was scared about publishing a series consistently.

Fiction needs dedicated upfront thinking, which doesn't work best with a weekly publishing schedule.

Once an episode was published, I couldn't go back and change things.

But while writing this series, I created a system that helps me overcome that.

The system:

  • Think about the characters and the theme upfront.

  • At any point, have +3 stories ready to be published.

  • Have a vague ending in mind.

This system prevented the urge to change things in already published stories.

So, what's next?

Frankly, I'm trying to figure it out. I will continue to write more short story series and also continue to evolve Level Up, but it will take some time to figure out what’s the next season of Level Up going to look like.

But in the meantime, I am going to merge my fiction and non-fiction "newsletters" into one. I had previously not done this to avoid sending irrelevant emails. But, it turns out that the people who read Zoom In, Zoom Out, are also likely to read Easy But Hard!

What do you think?

If you would like to follow along my work, do subscribe:

Thanks for reading :)


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